Melt 100 g (3½ oz) butter in a pan, add 500 g (1 lb 2 oz) shredded Belgian endives, 100 g (3½ oz) shredded white of leek and 125 g (4½ oz) sliced potatoes. Moisten with 1¾ litres (3 pt or 7½ U.S. cups) boiling milk, season with 15 g (½ oz) salt and cook gently together. Finish at the last moment with 100 g (3½ oz) butter and serve thin slices of French bread separately.